High image quality, high sensitivity, and treatment stability are demanded for silver halide color photographic materials for photography without distinction as to whether such are negative or reversal materials. As regards the image quality, sharpness, graininess, color reproduction, and the like are important, and as regards the treatment stability, it is important that a color reversal material has a good gradation balance whether it is standard development-treated (whose first development time is to the specification of a reversal article) or sensitization development-treated (whose first development is prolonged and/or temperature is raised).
It has been known that, in a multilayer color photographic material having blue-sensitive, green-sensitive, and red-sensitive silver halide emulsion layers, light scattering caused by silver halide grains in a silver halide emulsion layer is usually apt to lower the sharpness of emulsion layer positioned under the above-mentioned emulsion layer.
Color photographic materials having sharpness, sensitivity, and graininess improved by use of tabular silver halide emulsion grains are mentioned in U.S. Pat. No. 4,439,520. However, use of such a tabular silver halide emulsion causes a severe problem in a reversal treatment of negative type emulsion. A color reversal treatment obtains a color reversal image by black-and-white development (first development)-treating a negative type silver halide emulsion, and, after that, fogging the remaining silver halide and carrying out color development. The black-and-white developing solution contains a solvent for silver halides such as potassium thiocyanate, sodium sulfite, or the like, and it provides a development accelerating effect by a solution physical development. However, if tabular grains having photosensitivity mainly on the surface of grains are used, an apparent increase in sensitivity of color reversal image and a lowering in the maximum density of the same image caused by a solution physical development of non-exposed grains around developed silver formed in the initial period of development using a black-and-white developing solution became marked. As a result, gradation fluctuates widely and contrast is lowered, in particular, when a photosensitive material containing the above-mentioned silver grains is sensitization development-treated.
Tabular silver iodobromide grains having a low silver iodide content of 4.0 mol% or less which are typically used in a color reversal photographic material have a large solubility of grains in the solvent, so that the above-mentioned fluctuation in gradation and lowering in contrast become significant. Therefore, it is very difficult to utilize tabular silver iodobromide grains having such a low silver iodide content in a color reversal photographic material.